Advanced ceramic tubular type oil pump

ABSTRACT

An advanced ceramic tubular type oil pump includes a pump barrel, a plunger, an inflow valve, an outflow valve, wherein a ceramic layer that can resist heat, attrition and corrosion is lined onto an inner wall of a steel based pipe of the pump barrel; a plurality of slots are spacedly apart pre-provided on an outer surface of a rod body of the plunger, an alloy coating for resisting attrition and corrosion is sprayed to an outer surface of the rod body of the plunger, and a plurality of zirconia toughened alumina (ZTA) ceramic rings are inlaid onto the alloy coating in the slots.

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

The present invention relates to oil exploit equipment manufacturing technique in the oil field, and more particularly to an oil pump.

2. Description of Related Arts

Oil pump is the key equipment to elevate the crude oil by utilizing pressure difference between the front and rear side of the ball valve. The quality of the oil pump directly influences the yield and cost of the oil field and the common damage to the oil pump is corrosion, attrition and sand plug. The oil fields of China are being exploited for the third time. For increasing oil production, water, carbon dioxide and polymer are injected into the well, so that the well environment is becoming worse and worse, more and more corrosion materials are produced, the life span of the oil pump is shorter and shorter, so that the cost for oil exploitation is increasing every year. In order to prolong the life span of the oil pump, the current solution is to apply segmented sintering ceramic casing to the inner wall of the oil pump and outer wall of the plunger. This method can help with the attrition resistance, heat resistance and corrosion resistance, but the ceramic casing is easily get broken, cracked and misplaced, and shows low impact withstand capability, so that the performance of the oil pump degrades over time. Furthermore, the cost of the sintering ceramic is high and the yield of it is low.

SUMMARY OF THE PRESENT INVENTION

An object of the present invention is to provide an advanced ceramic tubular type oil pump, which can resist corrosion, attrition, high temperature, stain, wax, and sand plug, shows high impact withstand capability, and is low cost and large output volume.

Accordingly, in order to accomplish the above objects, the present invention provide an advanced ceramic tubular type oil pump, including a pump barrel, a plunger, an inflow valve, an outflow valve, wherein a ceramic layer that can resist heat, attrition and corrosion is lined onto an inner wall of a steel based pipe of the pump barrel; a plurality of slots are spacedly apart pre-provided on an outer surface of a rod body of the plunger, an alloy coating for resisting attrition and corrosion is sprayed to an outer surface of the rod body of the plunger, and a plurality of zirconia toughened alumina (ZTA) ceramic rings are inlaid onto the alloy coating in the slots; both ball and seat of the inflow valve and outflow valve adopt advanced ceramic.

In order to ensure a stable operation of the oil pump in a corrosion environment and reduce outflow resistance, an outflow port of a standing valve cover adopts a streamline and three-groove structure.

In order to increase area of liquid flow channel and accelerate fallback speed of the ball, a traveling value cover adopts open type three-groove structure.

For easy inlay and structural stability, the ceramic ring is composed of three arc ceramic slices of same specification.

The alloy coating of the outer surface of the rod body of the plunger is nickel-base alloy coating material, and a thickness of the alloy coating is less than 0.254 mm.

In order to ensure a sealing performance of the whole pump, a ceramic valve ball and YG13 valve seat are adopted.

The advantages of the present invention is that the an aluminum oxide ceramic layer is lined onto and integrated with the inner wall of a steel based pipe of the pump barrel, and a plurality of zirconia toughened alumina (ZTA) ceramic rings are inlaid onto the alloy coating of the surface of the plunger, so as to avoid the direct attrition between the alloy coating and the pump barrel, keep the constant best interval of the plunger for a long time, and stabilize the output liquid for a long period. In the mean time, the problems that the sintering ceramic ring applied onto the ceramic plunger is easily broken, has low impact withstand capability and high cost are also solved.

Via experiment, the zirconium oxide ceramic of the plunger and aluminum oxide ceramic of the pump barrel have the best friction pair; replacing stainless steel valve ball and valve seat with ceramic valve ball and valve seat increases the lifespan for over 5 times; the valve cover uses stainless steel material to resist corrosion; the traveling valve cover adopts open three-groove structure to increase the open and close speed of the ball valve, increase the filling degree of the output of the oil pump, enlarge the area of liquid flow channel, accelerate fallback speed of the ball. The outflow port of a standing valve cover adopts a streamline and three-groove structure to ensure a stable operation of the oil pump in a corrosion environment and reduce outflow resistance.

These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a half sectional view of the oil pump of the present invention.

FIG. 2 is an axial sectional view of the plunger of the oil pump.

FIG. 3 is a structural schematic view of the arc ceramic slice.

FIG. 4 is a structural schematic view of the standing valve cover.

FIG. 5 is the left view of FIG. 4.

FIG. 6 is a structural schematic view of the traveling valve cover.

FIG. 7 is the left view of FIG. 6.

Reference number and its name in the drawings: 1. coupling of pump barrel; 2. valve cover above plunger; 3. ceramic pump barrel; 4. upper traveling valve; 5. joint of inner thread plunger; 6. plunger; 7. traveling valve cover; 8; lower traveling valve; 9. pipe stopper of valve seat; 10. standing valve cover; 11. one-way standing valve; 12 lower coupling; 13. ceramic ring

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 and FIG. 2, the main bodies of both pump barrel 3 and oil pumping plunger 6 are tubular shaped cylinder of a certain length.

The outer layer of the pump barrel is made of steel; the inner layer that contacts and rubs against the plunger 6 is a ceramic layer lined onto the pump barrel. The smooth finish and straightness of the ceramic layer on the inner wall of the pump barrel meet operating requirement by using mill instead of calibration. The plunger 6 is a cylinder made of steel; the inner cavity of the cylinder is a passage for oil; a nickel-base alloy is coated on the outside layer with a thickness less than 0.254 mm, and ceramic rings 13 are inlaid onto the alloy coating of the surface of the plunger; the outer wall of the plunger 6 is closely attached to the inner wall of the pump barrel 3, so that the oil pump can suck the crude oil from underground.

Referring to FIG. 3, the ceramic rings 13 are composed of three arc ceramic slices of same specification, and are inlaid into the slots pre-provided on the body of the plunger, and is milled so that the size of it is consistent with the size of the plunger 6.

Referring to FIG. 4 and FIG. 5, the outflow port of a standing valve cover adopts a streamline and three-groove structure.

Referring to FIG. 6 and FIG. 7, the traveling valve cover adopts open type three-groove structure.

The present invention discloses a manufacturing technique for tubular type ceramic oil pump used for oil exploit equipment in the oil field, wherein a ceramic layer is lined onto the inner wall of the pump barrel and is integrated with the steel based pipe of the pump barrel; the oil pumping plunger is coated with nickel-base alloy and is inlaid with ceramic ring.

The outer casing of the pump barrel is steel cylindrical base pipe. An aluminum oxide ceramic layer is lined onto the inner wall of the pump barrel and integrated with the steel based pipe of the pump barrel via selfpropagating process. The smooth finish and straightness of the entire pump barrel are ensured and meet operating requirement by using mill instead of calibration. The plunger is cylindrical pipe made of steel, and the plunger is coated with nickel-base alloy and is inlaid with ceramic ring. By taking the advantage of small friction pair between the ceramic coating and ceramic ring, the attrition to the nickel-base alloy layer is reduced, the tightness of the plunger can be kept for a long time, the lifespan and output liquid can be increased, the operating cost is reduced, and the oil exploit efficiency and economic benefit are improved.

One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have been fully and effectively accomplished. Its embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims. 

What is claimed is:
 1. An advanced ceramic tubular type oil pump, comprising: a pump barrel, a plunger, an inflow valve, an outflow valve, wherein a ceramic layer that can resist heat, attrition and corrosion is lined onto an inner wall of a steel based pipe of the pump barrel; a plurality of slots are spacedly apart pre-provided on an outer surface of a rod body of the plunger, an alloy coating for resisting attrition and corrosion is sprayed to an outer surface of the rod body of the plunger, and a plurality of zirconia toughened alumina (ZTA) ceramic rings are inlaid onto the alloy coating in the slots.
 2. The advanced ceramic tubular type oil pump, as recited in claim 1, wherein an outflow port of a standing valve cover adopts a streamline and three-groove structure.
 3. The advanced ceramic tubular type oil pump, as recited in claim 1, wherein a traveling value cover adopts open three-groove structure.
 4. The advanced ceramic tubular type oil pump, as recited in claim 1, wherein the ceramic ring is composed of three arc ceramic slices of same specification.
 5. The advanced ceramic tubular type oil pump, as recited in claim 1, wherein the alloy coating of the outer surface of the rod body of the plunger is nickel-base alloy coating material, and a thickness of the alloy coating is less than 0.254 mm. 